Premature rupture of membranes refers to the rupture of membranes before labor, manifested as vaginal discharge and abdominal pain, among other symptoms. The diagnosis of premature rupture of membranes is primarily conducted through the following methods: First, based on the patient's symptoms. The most typical symptom of premature rupture of membranes is the discharge of clear fluid from the vagina. This can generally be identified as amniotic fluid by the naked eye, which helps in diagnosing premature rupture of membranes. Second, if the amount of vaginal discharge is minimal, PH test strips can be used for detection. A change in the PH strip may indicate a diagnosis of premature rupture of membranes. Third, an ultrasound can also generally assess premature rupture of membranes, as the amount of amniotic fluid will decrease when the membranes have ruptured. These methods combined can confirm the presence of premature rupture of membranes.